Repair of 220v welder fan motor

[kenmac]

Not to be glib, but for $20 I could just wire a 110 fan to a single hot leg and the ground. What's the advantage of the transformer?

By all means. If you feel you can do this. It's ok with me.This is almost the same type motor that is used to exhaust flue gasses from a gas furnace. They are built cheap & go out quite often due to bad windings

 

[joshuabardwell]

That type of fan is very common for many welders and bigger battery chargers. Since there is no white wire going to it, I would say it's 240 volt, but you'll have to check that to be sure. I'm sure you can find one online for less than $70. Check out Grainger.com. They have EVERYTHING, even the kitchen sink. They are a bit pricey, but it's a good place to start because they also list all the specs. Then you'll know what you need, and you can search the web for the best buy.

It's definitely 240v.

Thanks for the tip. I will try searching for the motor's part number instead of the welder's model number and "replacement fan." I couldn't find a direct replacement for less than about $70. Frankly, it surprised me that the fan was 240v at all, given what little work it has to do. But what do I know?

 

[Raspy]

I had what looks like the exact same fan in my Miller. When it went out I installed a 220V muffin fan from an electronics store.

Much better fan and should outlast me. It was a simple replacement with a little work on the bracket.

Muffin fans are very common and cheap. They are also much better quality. Mine is about 4 1/2" in diameter, probably blows more air and is quieter.

 

[joshuabardwell]

Much better fan and should outlast me. It was a simple replacement with a little work on the bracket.
Muffin fans are very common and cheap. They are also much better quality. Mine is about 4 1/2" in diameter, probably blows more air and is quieter.

Thanks for the suggestion. This is really helpful. If I need to replace the fan, I can do it without having to jury-rig a 120 or anything like that--and at a reasonable price too!

 

[Willl]

You try a little lube on the bushings ?, might buy you a little time to look for another.

 

[joshuabardwell]

I'm doing a little more googling, and I wonder if anybody could speak to the expected resistance across the leads of this motor? I have checked for a short to ground and found none. The next step in the troubleshooting flowchart that I found is to check resistance across the leads, and it says basically that you should have an open circuit. I get 33 ohms. Is that indicative of a failed winding?

 

[Rock knocker]

Not to be glib, but for $20 I could just wire a 110 fan to a single hot leg and the ground. What's the advantage of the transformer?

I wouldn't get involved in buying a transformer, there has to be a 220v fan that would work for a cheaper price than was quoted by the manufacturer.

One thing you probably should not do is tie to ground and create a 110v circuit. Chances are that your machine is a 3 wire 2 pole with ground machine. The ground is there as a safety, and is not meant to be used as a substitute for a neutral.

Tools like this and other machines like table saw are not like clothes dryers. Clothes dryers are 220/110v and use 110v for timers and lights. Machine tools, even those that can be tapped as either 110 or 220v, use just a single voltage at any one time.

 

[joshuabardwell]

One thing you probably should not do is tie to ground. Chances are that your machine is a 3 wire 2 pole with ground machine. The ground is there as a safety, and is not meant to be used as a substitute for a neutral.

That is correct. And you are right about 220v fans. It appears that "muffin fan" was the right term to use. Thanks, TBN!

 

[joshuabardwell]

BTW, this looks like a fine contender for a replacement. I wish I could find the approximate CFM of the original fan, to make sure it's up to snuff... but I'm sure it's up to snuff.

http://www.amazon.com/230V-AC-Cooli...d=1348199545&sr=1-3&keywords=230v+cooling+fan

 

[Raspy]

BTW, this looks like a fine contender for a replacement. I wish I could find the approximate CFM of the original fan, to make sure it's up to snuff... but I'm sure it's up to snuff.

Amazon.com: 230V AC Cooling Fan. 120mm x 25mm HS: Home Improvement

The easiest way to compare output is to simply look at the watts. The muffin fan will definitely be more efficient, so similar watts will equal a greater output. But simply being close is fine because the demand for cooling is so variable. I don't know what your fan draws, but the one shown is 13W.

You can always buy two of them and have twice the output. These fans are easy to work with, easy to mount, very reliable, cheap to buy and draw a low amount of power. Just mount two of them side by side if you want more wind. It's a no-brainer.